Reproducing wood graining and surface designs



Patented Nov. 5, 1935 REPRODUCING WOOD GRAINING AND SURFACE DESIGNSWallace W. Kirby, Joseph A. Scott,Jr., and Frank J. Wagner, Washington,D. 0., assignors to Plano-Finishing Company, Inc., Washington, D. 0., acorporation of Virginia.

No Drawing. Refiled for abandoned application Serial No. 433,176, March4, 1930. This application June 5, 1935, Serial No. 25,154

7 Claims.

Reproduction by photolithography which includes flat or plane surfaceprinting with socalled greasy ink or pigment, either direct from thegrained or other Water absorbent lithographic plate, or preferably bythe offset method by the use of a rubber blanket or apron, is veryeconomical as well as exceedingly faithful and accurate, and otherwisesatisfactory and desirable.

The print, drawing or picture to be reproduced. however, must meetpeculiar requirements of sharpness and clearness, for reallysatisfactory reproduction by photolithography, and so far as we havebeen able to learn and discover, the grain and varying tones andshadings of natural products, such as Wood, have not been, heretofore,successfully reproduced on the surfaces of other products byphotolithography to produce a satisfactory final product that faithfullysimulates the natural wood surface, because of such requirements, andthe problem has not been heretofore solved because of the failureheretofore, to recognize the necessity of first producing a completesharp picture or print of the grain and said tones of the natural woodof such character as to reproduce by photolithography without blotch andblue spots.

The general object of this invention, is to economically reproduce thevisible surface design of a natural product, such as wood, on anysurface .adapted to receive the same, and attain maximum accuracy andnaturalness in reproduction, and to produce a final product thatfaithfully represents and closely simulates a finished or polishednatural surface, such as wood, of desirable design.

And more specifically, a further object of the invention is to producesuch a clear detail print of a natural wood master pattern, by asuitable photographic process, that will reproduce by photolithographyin ink or pigment on a suitable surface primed to provide a field of thedesired color, bringing out in detail the varying tones of the naturalwood without blurs and blotches and color characteristics that by asuitable photographic method we produced a print showing the naturalwood grain graduating from dark gray to black, for instance, and inaddition, the varying tones of the natural wood graduating from nearlywhite to light gray, for instance, on a contrasting light, such aswhite, field. or ground, all in detail, without blurs or blotches. Thispicture, or so-called print, not only shows the natural wood grain, butin addition the color tones or lights and shades of the natural wood,with such distinctness and detail, as to enable us to accuratelyreproduce the same in suitable color on any suitable surface, as byphotolithography, and then so finish the surface bearing thereproduction, as, to all intents and purposes, duplicate a panel offinished natural wood in appearance and beauty.

From our experience based on our successful solution of the problemafter long experimentation and actual practice in the reproduction ofwood surface designs andgraining, we now prefer to employ theapproximate steps, -as follows, in carrying out our method, namely;

We first select the wood panel that we wish to reproduce. For thispurpose we usually select a suitable wood having a beautiful grain andtone design. The raw unfinished surface of this panel, uncolored exceptfor its natural wood coloring, is cleaned by the use of a suitableabrasive,

to remove dirt, foreign matter, stains, scratches,

and produce a smooth flat surface.

The clean smooth surface of the selected wood panel is then treated witha thin dye in the form of a stain that will not act as a filler to fillor 1 close the pores of the wood, and that will sink into but not coveror coat the wood surface and hence permit the contrasting or darkervarying shades or tones of the natural wood, to show through such stainand be recorded on the sen- 40 sitized photographic film. A dye isselected of a color closely approximating the predominating naturalactinic color in the wood. This dye is applied to the entire surface ofthe pattern to provide a field or background of a color that can bechanged in reproduction by a suitable photographic process to produce aprint or picture wherein the differently colored or shaded grain andtones of the wood are sharply defined, without blurs and blotches, on acontrasting, preferably, white or light colored field or background. Forinstance, red is the predominating actinic color of walnut and mahoganywoods, as distinguished from the darker colored tone variations andgrain, and hence where the master pat- 5 tern is composed of either ofthese woods we can apply thin liquid red stain to the entire surface ofthe wood providing a red field or background contrasting with the darkcolored grain and the dark tones and grain graduations which showthrough the red field, and the same is true, where dyes of other colorsare used to stain these or other woods to provide the contrasting fieldsof colors that can be recorded on the panchromatic or other colorsensitive film to produce a negative which when printed will show thewood tones and shadings as well as the Wood graining on a white or lightcolored field.

After the master pattern wood has thus been dyed to secure thecontrasting field, the surface thereof is sealed by the application of athin transparent coat of a suitable colorless sealing medium, such asshellac. The transparent shellac or other liquid sealing medium is ofthin liquid consistency and without filler or other characteristics soas not to fill or close the grain pores, as it is our purpose to keepthese pores open and unfilled. This thin sealing coating is appliedmainly to prevent the subsequently employed black or dark dye ofpigment, from staining the wood field or background and overpowering orfading out the red or other color previously applied thereto.

After the wood field has thus been dyed and sealed, the entire surfaceof the wood panel is covered with a dark or preferably black dye or asuitable black or dark pigment, to color the unfilled grain pores of thewood which thus are more or less sharply and in detail brought out in acolor that contrasts with the field, being non-reflecting, and will withthe field act on the color sensitive film through a color filter ofapproximately the same color or shade as the field, to produce theresult sought.

The coating or covering of dried dark or black pigment or othercoloringmatter on the Wood master pattern panel, is finally cut off orremoved to completely expose and uncover the red or other contrastingcolor field, by suitable means, as by rubbing with steel wool. The blackdye or pigment penetrates down into and colors the open grain pores, andis not removed when the surface black pigment is cut off and, hence, thedark colored grain pores stand out in the red dyed field, when the woodmaster pattern is completed. V

The dark color is, preferably, applied to the grain pores in the form ofa stain that does not fill and close said pores, as apparently betterphotographic results are thereby attained owing to the depths or hollowsof the pores below the plane of the red field, although the darkcoloring matter can be applied in the form of a pigment that does fillup and close said grain pores, with good photographic subsequentresults.

The natural-visible tones and shade graduations of thewood are caused bysurface portions of the wood that are in varying degrees more dense orrelatively harder than the remaining portions of the wood field, andhence of different color shades than said field, and also to varyingdegrees do not so readily take up and absorb the red or other fieldstain, as the remaining portions of the field. These tone and shadegraduations hence stand out in the red or other colored field, invarying degrees. 7

We thus produce a wood master pattern, the surface of which presents twopredominating'or major colors, jnamely;the red or other artificial- 1ycolored field; andthe artificially colored dark colored natural woodtones and shade graduations showing through or in the red field; allstanding out in contrast in the red or other colored field, in conditionto be accurately picked up and registered in detail on the colorsensitive film.

The master pattern is now ready for photographing, by any suitablephotographic process under which the red or other colored field is notpermitted to register or act on the sensitized film other than as red,or as whatever other field color is used and to thus appear on the finalprint as a white or light colored field; on the other hand under saidphotographic process, the dark grain portions and the dark tone andshade graduations do act on and are accurately and in detail recorded bysaid film. The final picture or plate thus produced will show the darkgrain design or pores in dark gray to black, for instance, and the toneand shade graduations of the natural wood, in light gray to white, forinstance, all on a white field. The picture produced by the peculiarphotographic process that employs a color screen and a color sensitivefilm, will accurately and in detail reproduce or show the dark coloredgrain design and the natural tone and shade graduations, of the woodmaster pattern on a field of contrasting color, a print or picture thatcan be accurately reproduced, by photolithography, on a suitable surfaceto attain the desired results.

As an example of a photographic process, that can be employed to producethe desired picture of the wood pattern suitable for proper reproductionon a proper surface by photolithography, we employ a commercial or othersuitable camera tophotograph the wood master pattern hereinbeforedescribed, by the use of a highly sensitive plate or film, preferably apanchromatic or other color sensitive film or plate, and a suitablecolor filter. For instance, where the field of the wood master patternis stained red, we employ ared color filter of the shade of the redstain, and thus protect the panchromatic plate from being acted onexcept by red, "by exposing said plate to action by the image we wish toreproduce, namely;- the black or dark grain and the tone and shade colorgraduations of the natural wood.

Where the field of the wood master pattern is of a different color thanred, we employ a correspondingly colored color filter to eliminate allbut such color from and enable the panchromatic film to record only thecontrastingly darker colored wood grain and tones, on a contrastingfield, such as white, as hereinbefore explained.

A print of the usually reduced photographic negative thus produced, willshow graduations of tone and shading of the natural wood pattern varyingfrom nearly white to light gray back ground in contrast with the grainof the natural wood in dark gray to black, reproducing faithfully thegrain figure of the wood and the natural wood color graduations of toneand shading, on a contrasting white or light colored field.

The photographic negative thus produced is then projected by anysuitable apparatus and methods such as employed in commercialphotography and photolithography, usually, to full size on colorsensitive photographic paper or other sensitizedplate, and a positiveprint or picture is produced therefrom.

From this projected print, a half tone or reticulated, or grained orother screen usually, wet plate negative is produced by any suitablemeans or black grain design or pores, and the dark and method,preferably such as are commonly employed in commercial photography andphotolithography.

By suitable apparatus and methods, such as commonly employed in surfaceprinting or lithography, the image of said half tone negative isreproduced on the water absorbent surface of a lithographic stone orplate to form the flat plane printing surface thereof. Usually, grainedzinc or aluminum lithographic plates are employed, and the transfer ofthe image from the half tone negative to the grained surface of theplate is accomplished by coating the grained surface with a sensitizedfilm of ammonium-bichromate in albumen, and properly arranging the halftone negative and the sensitized grained plate in a vacuum printingframe with the negative in contact with the sensitized surface andexposed to brilliant light. After the required exposure, and dissolvingand removing the unexposed portions of the sensitized film, and othertreatment followed in common lithographic practice, the hardened filmremaining on the grained plate constitutes thegreasy-ink-receiving-and-printing fiat surface of the plate and is afaithful reproduction of the hereinbefore described original photographof the prepared wood panel or master pattern.

The areas of the grained surface of the lithographic plate, not coveredby the image film that forms the flat printing surface are kept moistand in greasy ink repelling condition, and hence the greasy ink appliedafter each printing stroke, adheres to the printing surface and not tothe grained surface, and can be directly transferred from the grainedplate to the product to be printed.

However, we prefer to employ the offset process and apparatus, such forinstance as commonly employed in commercial lithography, for printing onthe product, we wish to produce, the reproductions of the originalphotograph of our said wood master pattern.

We can by the lithographic or fiat surface printing process, faithfullyreproduce the wood grain and tones, on the surfaces that have beenprepared for printing, of various natural and synthetic materials, suchas metal, compositions, and hard or compressed composition and otherwall boards and panels, etc.

The surface of the product to be produced in faithful simulation of thewood surface of the master pattern, is, preparatory to the printing ortransfer operation, first covered with a suitable priming or ground coatof pigment to constitute a field or background approximatelycorresponding in general color eifect to the predominating backgroundcolor of the natural finished wood of the master pattern when finishedwithout the red dye or other field color. Y

After this ground coat on the product has hardened, the imprint of themaster pattern wood grain and shading variations, in suitably coloredink or pigment, is deposited on said ground coat, by the flat surfaceoffset printing process as hereinbefore described.

After the ink has hardened, the ground coat and the ink imprint thereon,are preferably covered by a transparent sealing coating of varnish,shellac, lacquer, or the like, and any suitable finish or finishes canbe applied according to common finishing and polishing practice,toproduce a product having a surface in faithful simulation of thenatural finished wood, and this natural finished wood appearance isenhanced by the desired spacing or maintained separation of the dots ofink as imprinted by the flat surface printing process being the resultof the half tone, reticulated or lined negative.

This application constitutes a refiling of our application filed March4, 1930, Serial No. 433,176, for the same invention, the followingclaims being 5 those in the said original application Serial No.433,176, when said application was allowed September 26, 1932.

What we claim is:

1. In the method of reproducing the surface design of a natural product,on the primed surface of another product; those steps which includepreparing and variously coloring a master pattern'of the natural productto be reproduced to bring out the grain design and the tone and shadevariations of the natural product in contrast to the appliedpredominating field color of said pattern; then by a photographicprocess using a color filter of the approximate applied field color anda color sensitive film producing a print of said pattern sharply showingsaid grain design and said tone and shade variations in contrast on alight field; then reproducing said print in pigment on said primedsurface of the final product; and finally finishing said primed surfacethat bears said imprinted design in pigment.

V 2. In the method of reproducing the graining and tone and shade colorvariations of a natural product, on the surface of another product;those steps which include preparing a master pattern of the naturalproduct and coloring the same to produce a colored field with thedistinctively colored grain .and tone and shade color variationscontrasting with said field; then photographing the thus prepared masterpattern by the use of a panchromatic sensitized plate and a color filterof the color of said field; producing from said plate a sharp print ofthe natural grain and tone and shade variations of the master pattern;then reproducing a print from said plate, and then by a 4 suitableprocess reproducing said print in pigment on said surface of anotherproduct.

3. In the method of reproducing the graining and tone .and shade colorvariations of a natural product on the surface of another product byprinting; those steps which include preparing a master pattern surfaceof selected natural wood; artificially coloring said pattern surface toproduce an approximate single color field with the natural wood colortone and shade variations visible in said field; coloring the grainpores of the wood pattern to contrast with the field color; by aphotographic process using a color filter and color sensitive film,producing a print of said distinctly colored graining and of said toneand shade variations of the master pattern on a light colored field; andthen by photolithography reproducing said print in pigment on thesurface of said product.

4. In the method of reproducing a natural wood surface design on anotherproduct; those steps which include preparing a wood master pattern;dyeing the surface of the pattern to a field color through which thedarker natural wood tone and shade variations are visible; applying atransparent seal to the pattern surface; applying a contrasting color tothe pattern surface to darkly color the grain pores; then removing thedark color from the pattern surface to uncover the colored field; thenby a color sensitive photographic process, preparing a print, forsubsequent reproduction on said product of the contrasting graining andtone and shade variations on an approximately white field.

5. In the method of reproducing the graining printing on the suitablycolored surface of the product to be finally produced; those steps whichinclude selecting and preparing the surface of a natural wood panel toform a Wood master pattern having the graining and tone and shadenatural wood color variations visible in and through and in contrast tothe field of the pattern; then by a color sensitive photographic processincluding the preparation of a half tone line or screen negative,producing a print of said pattern surface showing the grain inapproximate dark gray to black and the tone and shade variations inapproximate light gray to white all on a white field; and finally byplane surface printing whereby the spacing of the dots of pigment ismaintained, reproducing said print in pigment on said surface of theproduct and finishing said surface bearing said imprinted pigment intosimulation of the master pattern surface.

6. In the method of producing on the surface of a product the naturalornamental surface design of a wood master pattern; those steps whichinclude artificially coloring the entire surface of the natural woodpattern with a primary color to the approximate natural wood color andcoloring the grain pores to contrast with the predominating field colorof the pattern surface; then by a photographic process employing a colorfilter and tone and shade color variations of wood by' of the color ofsaid field and a color sensitive film producing a print of said coloredgraining and variations; providing said surface of the product with aground color approximating the field color of natural wood as finishedby usual wood finish ing methods, and by photolithography reproducingsaid print in pigment on said ground color on the surface of theproduct; and then finishing said surface.

7. In the method of reproducing the graining and tone and shadegraduations of the surface design of the natural wood of a masterpattern on the surface of another product; those steps which includedyeing the surface of the natural wood master pattern to produce a redor other field approximating the predominating color of the natural woodfield without filling the grain pores of the wood with the tone andshade color variations visible in said field, and then applying acontrasting dark color to the grain pores; by a photographic processproducing a print of said contrasting or dark color portions and toneand shade variations, solely, of the pattern surface design; then byphotolithography reproducing said print in pigment by the fiat surfaceoffset process on the surface of the product.

WALLACE W. KIRBY. JOSEPH A. SCO'II, JR. FRANK J. WAGNER.

